This is a pretty strange scenario that I can not seem to solve. I have a stout in one of my kegs, currently on the line. It was pouring fine for about 3 days, I served up maybe 5-8 pints or so, then went out of town. When I returned, the faucet would not pour at all. I checked the gas, took apart the liquid out, pulled the dip tube to make sure it wasn't plugged somehow, put it all back together, and it still won't pour. The keg is pressurized, I am just getting nothing out of the liquid out line. Any ideas??